Fire alarm apparatus



Feb. 13, 1945. BATES 2,369,521

FIRE ALARM APPARATUS Filed Aug. 16, 1943 s Sheets-Sheet 2 F/GZ Feb. 13, 1945. E. F. BATES FIRE ALARM APPARATUS Filed Aug. 16, 1943 3 Sheets-Sheet 3 Inventor Mrs! ficdzriz/i Ba/wrsv Attorney mwl Patented Feb. 13, 1945 FIRE ALARM APPARATUS Ernest Frederick Bates, London, England, assignor to Standard Telephones and Cables Limited, London, England, a British company Application August 16, 1943, Serial No. 498,852 In Great Britain September 12, 1942 4 Claims.

This invention relates to fire alarm apparatus and more particularly to apparatus for registering impulses by punching a paper tape. The invention is also applicable to ambulance systems which are arranged similarly to fire alarm systems.

It is usual to provide at a fire alarm station a magnet connected so as to be energised each time a relay in a fire alarm circuit responds to the opening of this circuit or placed in a closed fire alarm circuit so as to respond to the opening thereof and arranged so that at each energisation (or de-energisation) the armature controls a mechanism for punching a hol in a paper tape.

As each substation or fire alarm box transmits, in the case of an alarm, impulses arranged according to a distinctive code, the holes in the tape provide a record of all alarms received and of their origin. The holes in the paper tape are usually triangular in shape. It has been the practice hitherto to push the armature of the magnet away from the paper by mechanical means and to provide a clockwork mechanism set in operation by the response of the magnet to feed the paper during a time determined by the movement of a member driven by a worm.

According to the present invention, the circuit of the electromagnet operating to punch a hole in the paper tape of a recorder of fire alarms is interrupted after a predetermined interval by a slow-operating relay, the circuit of which is closed simultaneously with that of the said electromagnet.

Both the electromagnet and the slow-operating relay may take the form of ordinary telephone type relays, a triangular shaped punch being fixed to the armature of the former. Conveniently the electromagnet, slow operating relay and a paper roll are mounted as a unit in rear of apparatus panel. The paper tape, after being punched passes through a slit to the front of the panel, along the front and passes through another slit to the rear of the panel where it passes between feed rollers driven by an electric motor, also mounted in rear of the panel. The circuit ofthe electric motor is closed on the first interruption of the fire alarm circuit and remains closed for a predetermined time after the last interruption.

The nature of the invention will be better understood from the following description taken in conjunction with the accompanying drawings in which Fig. 1 is a diagram of circuit connections;

Fig. 2 shows the manner in which the electromagnet, slow operating relay and paper roll are mounted as a unit, Whilst Fig. 3 is a plan view showing the manner in which the unit shown in Fig. 2 is mounted on a panel, together with an electric motor for feeding the paper tape.

Referring to the drawings, Fig. 1 show the two legs a and b of a fire alarm loop connected to two relays FA and FB and batteries BI and B2 in the manner described in British Specification No. 5819/42. Relay FA responds to signals over the fire alarm loop. At each response of relay FA contacts fal close circuits for an electromagnet EM and a slow operating relay AR, the circuit for magnet EM being made over normally closed contacts arl of relay AR. After an interval relay AR operates and breaks the circuit of magnet EM.

The magnet EM and relay AR are mounted as shown in Figs. 2 and 3 in a fire alarm station. Both electromagnet EM and relay AR are formed as telephone type relays and are mounted upon a panel l2 in the manner usual with such relays, apertures l3, l4, [5 being provided in the panel through which the terminal tags of the relays protrude. Mounted in one of the apertures I5 and supported at right angles to panel l2 by a bracket I6 is a paper guide II. A roll I-8 of paper tape is supported in rear of panel l2 on a bracket 19. The paper tape 20 emerges from the guide I! adjacent to the end of the armature I 0 of magnet EM. The end of this armature I0 is bent as shown and a punching blade II is fixed thereto. Each time magnet EM is energised armature I0 is attracted and blade ll punches a triangular hole in the tape 20. When relay AR operates, magnet EM is denergised and the blade I0 removed from the tape 20 by the customary retracting spring.

Panel I2 is supported a short distance in rear of a front panel 2| (Fig. 3). Paper tape 20 passes through an aperture 22 in panel 2| to the front of the panel and again through another aperture 23 to the rear of the panel 2|, being guided by rollers 24. The length of tape 20 in front of panel 2| is sufiicient; to display the complete code of a fire alarm substation.

The tape 20 is drawn along by feed rollers 25, 26 held together in a frame 28. One of the feed rollers is driven by an electric motor 21. The motor 21 is set in operation on the first response to a break signal from the loop a b Fig, 1 and remains in operation until a predetermined time after the last opening of the loop. Circuits for effecting this are shown in Fig. 1 and are as follows. The electromagnet EM that operates the punch also closes, on its energisation contacts eml. These contacts operate relay B, which at contacts bl, closes the circuit for the motor 21.

Contacts b2 of relay B prepare a circuit for relay D over normally closed contacts el. When the magnet EM is de-energised, contacts eml open and relay D operates in series with relay B. Relay D in operating opens contacts dl and breaks the circuit of a normally operated relay C. Relay C de-energises slowly and after an interval releases its armature to open contacts cl, breaking the circuit of relay E. Relay E de-energises slowly and after an interval, thus breaking the armature to open contacts el, thus breaking the circuit of relay B and D, if EM has not again been energised. Relay B in releasing opens the motor circuit. The time lapsing between the operation and release of relay B, during which the circuit of motor 21 is closed is sufficient to draw the portion of the paper tape that has been punched to the front of panel 2|. If the magnet EM is operated a second time before the motor circuit is broken, relay B remains operated, even if relay .E has released, relay D remains unoperated, keeping relays C and E operated, until magnet EM is de-energised whereupon the cycle of operations begins again. Thus the circuit of mo tor 21 is kept closed until the punched hole representing the last impulse received .is displayed in front of panel 2!.

The length of tape displayed in ,front of panel 2! is more than sufficient to display the longest code signal received and as the motor .21 feeds the tape some distance past the punching point after a code of impulses has ceased, there is an unpunched portion of the tape between the representations of successive groups of code signals.

When using the arrangement shown with the system described in which two relays FA, F3. are connected in the loop a b, a second punching magnet and .slow operating .relay is provided responsive to impulses received by relay FE and these are mounted on the panel 12 above the electromagnet EMvand relay AR in Fig. 2 in such .a way that the same paper tape 20 is punched :by the second electromagnet but-in a different position on the tape. The relay "3 would then be operated by contacts of this second electromagnet in parallel with contacts eml,

The auxiliary relays B, D, C and E may be mounted on panel I2 between relay AR and the motor 21. One of these relays B is shown in Fig. 3, the others have been omitted.

What is claimed is:

1. A fire alarm or like system comprising a normally closed signal-circuit, a relay having normally open contactscontrolled-thereby, arecorder operating circuit controlled by said contacts, a recorder actuating magnet and a slow operating relay energized bythe recorder operating circuit,

said slow operating relay being arranged to open the circuit of the actuating magnet after a predetermined time interval, motor driven means for feeding a recording tape into operating relation to the magnet including a motor energizing circuit and a relay for controlling said circuit, said relay being controlled by two parallel circuits, one circuit controlled by said slow-operating relay while the second circuit after having been initially energized by said first circuit remains energized for a predetermined time independent of the energization of said first circuit.

2. A fire alarm or like system comprising a normally closed signal circuit and a relay having normally open contacts controlled thereby, a recorder operating circuit controlled by said contacts, a recorder actuating magnet and a slow operating relay energized on closing of the recorder operating circuit, said slow operating relay having a contact connected to open the circuit of the actuating magnet, motor driven means for feeding a recording tape into operating relation to the actuating magnet including a motor energizing circuit and a relay for controlling said circuit, circuit means for energizing the motor control relay connected to be closed by a contact of the actuating magnet, said motor control magnet having a contact in a motor control circuit connected in locking relation to the motor control magnet and including therein a series relay and a normally closed contact of a slow release relay, a second slow release relay in a normally closed circuit including a normally closed contact of the series relay and said first slow release relay having an energizing circuit including a normally open contact of said second slow release relay whereby the opening of the motor energizing circuitis retarded by the action of the slow release relays operating in cascade relation.

3. ,A system according to claim 1, wherein said second circuit is controlled by contacts of the relay for controlling a motoreenergizing circuit, and by further contacts operated by a time-delay circuit for a predetermined time interval after said first contacts have been operated.

4. A system according to claim 1, wherein .said

second circuit is controlled by contacts of the relay for controlling a motor-energizing circuit,

and by further contacts operated by a time-delay circuit for a .predetermined time interval after 

